As a film or sheet used for wrapping of foods, medicinal products, daily groceries and the like, molded articles obtained by extrusion-molding an ethylene based polymer are often used. Among ethylene based polymers, a linear copolymer composed of ethylene and α-olefin, so called linear low density polyethylene, is excellent in impact strength as compared with a high pressure low density polyethylene. Thus, a wrapping material composed of a linear low density polyethylene can be made thinner as compared with a wrapping material composed of a high pressure low density polyethylene.
However, as compared with a high pressure low density polyethylene, a linear low density polyethylene is poor in transparency in some cases, and has lower melt tension in comparison with a high pressure low density polyethylene, and manifests wrinkling of a film by vibration of a bubble in blown film molding, and increase in the distribution of a film thickness (hereinafter, they are referred to as moldability). Therefore, methods for improving transparency and moldability of a linear low density polyethylene are investigated, and, for example, there is suggested a polymer composition obtained by blending 5 to 30% by weight of a high pressure low density polyethylene into a linear low density polyethylene (for example, Japanese Patent Publication of Examined Application (JP-B) No. 62-3177, Japanese Patent Application Laid-Open (JP-A) No. 11-181173).
However, in the above-described polymer composition, though transparency and moldability are improved by blending a high pressure low density polyethylene, impact resistance thereof significantly lowers in some cases, that is, the above-described polymer composition is not necessarily fully satisfactory.